Change-speed transmission control means



Oct 1945. G. T RANDOL CHANGE SPEED TRANSMISSION CONTROL MEANS Original Filed Dec. 28-

, 1940 5 Shets-Sheet 1 w m& I v&

47' TO RA/E K G. T. RANDOL 2,386,174

Original med Dec. 28, 1940 .5 Shets-Sheet 2 m ,-/7 'o/a GAE/WV f FH CHANGE SPEED TRANSMISSION CONTROL MEANS Original Filed Dec. 28, 1940 5 Sheets-Sheet 3 8 a. T. RANDOL 2,386,174 r Oct. 2, 1945. G. T. RANDOL Y 2,386,174

CHANGE SPEED TRANSMISSION CONTROL MEANS Original Filed Dea. 28, 1940 5 Sheets-Sheet 4 Guy/v T 194M004,

Oct. 2, 1945. G. T. RANDOL CHANGE SPEED TRANSMISSION CONTROL MEANS 5 Sheets-sheaf 5 Original Filed Dec. 28 1940 Patented Oct. 2, 1945 fUNlTED STATES PATENT OFFICE aasaru I CHANGE-SPEED TRANSMISSION CONTROL I -1HIANS Glenn T.'Randol, St. M1,, M0.

Continuation of application Serial No. 372,048, December 28, 1940. This application January 15, 1944, Serial No. 518,327

36 Claims. '(Cl. 192-35.)

This is a continuation of my application for Change speed transmission control means, Serial No. 372,048,1lled December 28, 1940.

My invention relates to change speed transe missions for motor vehicles and more particu-- larly to improved control means therefor.

One of the objects ofmy invention is to provide member in a predetermined position and moving,

' a control member such as. the clutch pedal or I its equivalent. v 1

Another object of my invention is to provide an improved control means for a conventional three speed forward and reverse gear ratio transmission which will enable the driver to obtain low and reverse speed ratios by the usual movements of a gear shifting lever and clutch pedal and to obtain either second or high speed ratios by setting said lever in a single predetermined position and then operating the clutch pedal, said speed control elements or a transmission and to control said power-operated means by the clutch pedal or its equivalent in combination with means for selecting the speed ratios in accordance with the condition of a speed responsive device.

A still further object of my invention is to provide an improved transmission control mechanism of the type referred to which is so con-' structed that it can be easily and quickly associated with a standard manually shifted change speed transmission as a replacement accessory and thus permit said transmission to h ave its speed ratios changed by the driver in an easier, safer, and more efficient manner.

Another object of my invention is to produce an'improved change speed transmission control mechanism which is cheap to manufactureand second or high speed ratio being selectively controlled by a speed responsive device.

Yet another object of my invention is to provide a control means for a change speed transmission which will permit the driver to obtain, by operating a member, one of several speed ratios which are selective by a speed responsive device.

Another object is to provide improved valve means for controlling the speed of movement of a power-operated piston employed to perform the shifting operation whereby the rate of travel of said piston may be retarded while passing through the neutral position in changing from one speed ratio to another, and thus permit the usual synchronizing mechanism of the transmistransmission to facilitate gear ratio changing and also to insure that the operator of the vehicle can be certain of the neutral condition of the transmission when such is desired.

Another object of my invention is to provide power-operated means for shifting the change interlocking which provides the vehicle operator with all the desirable features of both manual and automatic gear shifting control and at the same time permits the continued use of the wellknown and reliable change speed gearing embodying interchangeable gears and clutches.

Other objects of my invention will become apparent from the following description taken in connection with the accompanying drawings in which Figure 1 is a, side view of a change speed transmission having associated therewith a control mechanism embodying my invention, the parts being in neutral position; Figure 2 is a perspective view of the steering wheel mounted hand lever and associated indicating bracket; Figure 3 is a side view similar to Figure 1 with parts in section and the control, mechanism in low gear position; Figured is a partial sectional side view ing in neutral position and the control mechanism set for automatic operation oi. second and high speeds; Figure 7 is a viewsimilar to Figure 6, showing the parts moved to high speed position; Figure 8 is a sectional view taken on the line 8-8 of Figure 6, showing the governor-controlled valve in second gear position; Figure 9 is a sectional view taken on the line 9-9 of Figure 6 and showing the governor-controlled valve in high gear position; Figure 10 is a view taken on the line ill-I0 of Figure 9, showing certain parts of the control mechanism in neutral position; Figure 11 is a sectional view of the clutch and synchronizing means for high and second speed gear ratios with the parts in high speed positions;

Figure 12 is a, sectional view showing the manner in which part of the control mechanism is mounted on the steering column; Figure 13 is a view taken on the line I3--l3 of Figure 12, parts being shown in section; Figure 14 is a view taken on the line |4--|2 of Figure 12; Figure 15 is a sectional view of the governor valve, said view being taken on line |5-|5 of Figure 8; Figure 16 is a perspective view of the governor-controlled valve member; Figure 1'7 is an enlarged view of the valve structure as shown in section in Figure 3; Figure 18 is a perspective view of the hand-controlled shut-off valve; and- Figures 19 and 20 are enlarged views of the combined interlock and yieldable detent means between the shifting forks as seen in Figure-10.

My improved control mechanism is especially well adapted. for controlling a standard change speed transmission having three forward speeds and a reverse gear. I have, therefore, shown my control mechanism associated with such a change speed gearing but it is to be understood that it can be easily adapted for controlling other types of change speed transmissions.

Referring to Figures 1, 6 and 11, the numeral I indicates the engine for driving a motor vehicle, this engine being'connected to the wheels of the vehicle by means of the usual clutch (not shown) enclosed within the housing 2 and controlled by the clutch pedal 3 andby means of the change speed gearing generally indicated by the numeral 4. The gearing is connected through suitable shafting and a differential gear to the vehicle wheels as is the usual practice. The change speed gearing is embodied in a housing 5 in which is journaled the driving shaft 6 (con nected to one element of the main clutch) and the axially aligned driven shaft 1. The portion of the driving shaft within the gearing housing has secured thereto a gear 8 constantly meshing with a gear 9 of a cluster of gears mounted on a counter-shaft I journaled in the housing at one side of the driving and driven shafts. The cluster of gears, in addition to the gear 9, includes a second speed gear II, a low speed gear |2,'and a reverse speed gear stant mesh with an idler gear It. A portion of the driven shaft 1 which extends into the housing is provided with splines l upon which is slidably mounted a combined low and reverse gear It, said gear, when moved forwardly, meshing with the gear |2 to obtain low speed ratio, andwhen moved rearwardly, meshing with gear M to obtain reverse gear drive.

The driven shaft I ahead of the splined portion has rotatably mounted thereon a second speed gear II which is in constant mesh with the second speed gear on the counter-shaft. The second speed gear I1 is connected to the driven shaft and the driven shaft is connected to the driving shaft in a selective manner by means of a combined clutch and synchronizing means. This structure is well known and need only be briefly described. As best shown in Figures 6 and 11, clutch teeth l8 are provided on the driving shaft and clutch teeth l9 are provided on the gear said teeth being in opposed spaced relation. The portion of the driven shaft between the clutch teeth has secured thereto a splined sleeve 20 having thereon a slidable clutch collar 2| provided with internal teeth for cooperating with the teeth l8 when the sleeve is moved forwardly, or for cooperating with teeth I! when moved rearwardly. The synchronizing means which is employed to bring either the teeth l8 or IE andthe internal teeth of the collar 2| to substantially the same speed at the time they are engaged comprises synchronizing means 22, one associatedwith the l3, the latter being in con-- driven shaft" teeth is driven shafts together and then subsequently.

permit the movement of the collar through the teeth of the synchronizing member to a position engagingteethl-S. Similarly, when collar 2| is moved rearwardly, members 23 will be operated to move the synchronizing member 22 so as to frictionally connect gear I! to the driven shaft and then subsequently permit the teeth of the clutch collar to pass through the teeth of the synchronizing member and engage teeth |9.' In Figure 6 the clutch collar 2| is disengaged from both teeth i and I9 and in Figurell the clutch collar is shown asbeing moved forwardly to a position where the driving shaft is directly connected to the driven shaft.

In accordance with my invention I have provided improved means for shifting the collar 2| and the combined low and reverse gear IS in order to properly control the change of speed ratios of the transmission. In the side closure plate 24 for the gearing housing 5 there is journaled a shaft 25 (best shown in Figure 8) which extends to the exterior of the closure plate and has pinned thereto an operating arm 25. The inner end of this shaft has secured thereto, as by welding, an upwardly extending arm 2! in which is journaled a shifting fork 28 engaging in an annular groove in the combined low and reverse gear IG. Thus when the arm 26 is moved to rotate shaft 25 in a counter-clockwise direction, as viewed from the exterior of the closure plate, the shifting fork 28 will be so moved as to place the gear IS in mesh with thegear l2 to provide low speed ratio and when the arm is turned in the opposite direction, the shifting fork will move to cause the gear IE to be placed in mesh with the idler gear M to obtain reverse gear ratio.

Also journaled in the closure plate forwardly of the shaft 25 is a second shaft 29 (best shown in Figure 9) and'secured to the outer end thereof is a-second arm 30 for rotating the shaft. The inner end of the shaft has secured thereto, as by welding, an upwardly extending arm 3| in which is pivotally mounted a shifting fork 32 engaging in a groove in clutch collar 2 I. Thus when the shaft 29 is rotated in a counter-clockwise direction, as viewed from the exterior of the closure plate, collar 2| will be moved forwardly to cause the driving shaft 6 to be connected directly to the driven shaft 1 to provide direct or high speed ratio, and when the shaft 29 is rotated in the opposite direction, the collar will be moved rearwardly to cause gear to be connected to the driven shaft to provide second speed ratio.

As best shown in Figure 10 (a view of the inside of the closure plate) the closure plate 24 has mounted thereon two companion neutralizing levers 33 and 34. The lever 33 is secured to a shaft 35 journaled in the plate, and the lever 34 is rotatably mounted on a pin 36 carried by the plate. These levers extend upwardly on opposite sides of the arm 3| in which the shifting fork 32 is pivotally mounted. The lever 33 is provided with an integral arm '31 and lever 34 is provided with an integral arm 38, the latter having a circular portion for reception in a circular cutout in the former whereby the two levers will be caused to move together and in opposite directions. The levers are rotated by, means of an arm 39 on the exterior end of shaft 36. The construction is such that when arm 33 is turned so as to move the levers toward each other. they will cause the shifting fork 32 to be moved to its central or natural position whereby the clutch collar can be positively disengaged from either teeth l8 or I9'if engaged with either set of teeth. When arm 39 is operated to spread the levers 33 and 34 apart, the shifting fork 32 is then free to be moved by arm 30 and shaft 28.

When the levers 33 and 34 are spread apart to their limit of outward travel they will be positioned somewhat beyond the arm 39 when in an operative position. This condition is shown in Figures 4 and 5.

The arm 33 for controlling companion levers 33 and 34, and arm 28 for rotating shaft 25 and moving the combined low and reverse speed gear l6, are both adapted to be controlled from a remote point by means of a single member, said remote point preferably being adjacent. the

. steering wheel of the vehicle. The means for controlling these two arms is best shown in Figures 1, 2, 12, 13 and and comprises a rod 40 connected to arm 39 and a rod connected to arm 26. These rods extend forwardly and upwardly and are connected at their upper ends to arms 42 and 43 mounted on the lower end of a shaft 44 positioned parallel to the steering column 45. The lower end of shaft 44 is journaled in a bearing 46 for both rotative and sliding movement, said bearing being carried by the lower end of the steering column. A cover 41 is. provided to en-' at the end of the leg of the slot marked Lo. the arm 43 will be operated and through rod 4|, arm

I 23 will be rotated in a counter-clockwise direction, as viewed in Figure 1, to thus shift the combined low and reverse gear II to a position where it meshes with the low gear l2 on the countershaft,

thus giving low speed by means of a manual operation. When handle BI is moved to a position to place the finger at the end of the slot marked R, arm 43 of rod 4| will rotate arm 24 in the opposite direction and cause the combined low and reverse speed gear to be moved to a position where it meshes with the idler gear and thus cause reverse gear to be obtained. When the The upper end of shaft 44 is mounted in a bracket 5| in order to have both a rotative' move- 'ment and a sliding movement with respect to said bracket. This bracket is carried by the steering column just beneath the steering wheel 52. The bracket has a portion 53 which extends forwardly and upwardly beneath the steering wheel and thisportion is provided with a'Y-slot 64. The ends of each leg of the slot are designated by let- .ter R, Lo and Hi as clearly shown in Figure 2. Thecentral part of the Y-slot at the point where the legs meet is designated by the letter N. The upper end of shaft 44 has secured thereto a handle extending outwardly to the right side of the steering column, and carried by, this handle is an integral indicating finger 58 extending into the Y-slot. A spring 51 is interposed. between lever 55 and bracket 5| in order to normally bias shaft 44 downwardly and to a position where pin 48 engages slot 49 to connect the shaft to arm 42. The biasing action of the spring causes the finger to enter the leg of the slotmarked Hi when the fingerls at the N position. To connect shaft 44 to arm 43 it is necessary to move shaft 44 upwardly by lifting on the handle and this can only be done when'handle 55 is in a position where the finger is opposite the N position. When the handle is rotatedin the direction from the N position to placethe finger handle is moved to place the finger opposite the position marked N, spring 51 will cause shaft 44 to be moved downwardly so as to connect this shaft to arm 42, this connection being the normal mechanical connection between the shifting handle 55 and the transmission as already noted. When the handle is moved to place the finger I.

. at the end of the leg of the slot marked Hi," arm 39 will be rotated'to spread levers 33 and 34 apart, as seen in Figures 4 and 5.

The means employed for shifting clutch collar 2| for obtaining direct drive (high speed ratio) or second speed ratio comprises a suction-operated motor 53 mounted adjacent the exterior of the closure plate by means of a, bracket I59. This motor includes a cylinder 3|) having reciprocable therein a piston 3| which is connected by a piston rod 62 to arm 30 for rotating, shaft 29 which controls shifting fork 32 for the clutch collar 2|. When the piston of the section motor is centrally positioned in cylinder 60, the shifting fork will be in a .central position where the clutch collar 2| is disengaged from both teeth |8.and l3. This position of the piston is indicated in Figures 1 and 6 and is the neutral position. When the piston is moved to the forward end of the cylinder, shaft 29 will be so rotated as to cause the shifting fork 32 to move the clutch collar 2| forwardly and connect the driving shaft directly with the driven shaft. When the piston is moved to the rear end of the cylinder, the shifting fork will be so moved as to shift the collar rearwardly and connect the second shaft.

The source of suction for operating the suction motor is that present in tl e intake manifold of the engine and in order to control the suction and properl operate the suction motor to speed gear I! to the driven perform t -e shifting of the clutch collar, there are provided four valves generallyindicated by the letters A, B, C and D. I The valve A is adapted to be controlled by clutch pedal3, the conditioning valve B by lever 34 of the two companion levers mounted on the inside of the closure plate, the valve C by the shifting fork 32, and the governor controlled valve D by a speed responsive device whichis preferably driven from the countershaft of the gearing although it may be d.iven from the driven shaft of the vehicle if found desirable. In the preferred arrangement of the valves the governor-controlled valve D is placed next to the suction motor in the line of communication between the manifold and said The speed responsive device for controlling this valve is mounted in, a casing 63 motor.

secured to the side of the transmission housin opposite t-at of the closure plate 24 (see Figures 8 ard 9). The casing is provided with a guide portion 64 screwed into the transmission casing, said guide portion acting as a bearing for a shaft 65 having. a gear 66 on its inner end meshing 83' is attached to casing 63 in which is an atmospheric porthole 'I'I' covered by a screen, I

The sleeve 89 is grooved and receives an arm 12 of a valve element 13 slidable in a bore 14 of the housing 63. This-pore has a port 15 which is connected by a conduit 16 with the rear end of cylinder 60 of the suction motor. The bore is also provided with a port 11 which is connected by a conduit 18 with theforward endof cylinder 50 of the suction motor. A third port 19 positioned intermediate ports 15 and 11, is connected by a conduit 80 with the valve C. A passage 15' places the inner end of bore 14 in communication with the interior of casing 63., The valve element 13 (shown in detail in Figure 16) is of cylindrical construction and provided with recesses 8| and 82 adapted to communicate witheach other by an intermediate cut-away portion 83. The recesses 8| and 82 are so spaced apart as to selectively connect central port 19 with ports 15 and 11. When the fly-weights 68 are adjacent the shaft, the valve element will be so positioned that conduit 18 will be connected with conduit-80, thereby placing the rear end of cylinder 50 in communication with the source of suc- 'tion. These positions of the valves and weights are shown in Figure 8. When the weights 68 are thrown outwardly by a predetermined speed of rotation of the counter-shaft of the gearing, the valve element will be so positioned that conduit 18 will be connected with conduit 80, thereby placing the forward end of the cylinder of the suction motor in communication with the source of suction. Thesepositions of the valve elements and weights are shown in Figure 9. In practice the position of the fly-weights in Figure 9 will not be obtained until the countershaft is rotating at a speed which is equivalent to about 18 miles per hour vehicle speed. This condition can be varied by adjusting the tension of spring 10.

The three valves A, B and C are all mounted as a unit on the exterior of the closure plate 24 and are arranged between conduit 80 leading from the speed responsive valve D and conduit 84 leading to the manifold, valve A being closest to the manifold, valve B next, and valve C third. The relationship between the three valves and their positions on, the closure plate is best shown in Figures 3, 4 and whereas Figure 1'7 shows an enlarged sectional view of the three valves. The valves are all mounted in a single casing 85 which has at its forward end a vertical bore 86 in which valve element 81 of the pedal controlled valve A is r'eciprocably mounted. This valve element is formed on the end of a square rod 81' which is slidable in a square guide axially aligned with the bore 86. The lower end of the rod carries a roller 88 which is engageable by an arm 89 integral withthe clutch pedal 3.- The valve element 81 is biased to its lower position by a spring 98 interposed between the valve element and a closure plug 9| which has an air relief' opening92 therein closed by a screen 93. The

valve element 81 is formed with an annular recase 94 for placing the port 95 connected to the conduit 84 leading to the manifold with the passage 96 leading to a bore 91 which is at right angles to bore 86. The bore 91 is also connected by a passage 98 to bore 86 at a point above the passage 95. The valve element 81 also has a cutout portion 99 which permits passage 98 to be in communication with the atmosphere through the opening 92 at the upper end of bore 96. This cutout portion is also capable of connectingthe passage 95 to the atmosphere when the valve element 81 is in its lower position where it is normally biased by spring 90. When in its lower position the valve element also positions the annular recess portion 94 so that port 95 and passage 96 are cut off from communication with each other. The lower position of the valve element 85 is shown in Figure 3, and its upper position is shown in Figures 4, 5 and 17.

The cross-bore 91 receives a cylindrical valve element I00 (shown in perspective in Figure 18) which is the movable valve element of the conditioning valve B. This valve element carries an arm ml which is connected to neutralizing lever 34 by'means of a slot I02 receiving a pin I03 carried by the lever. The valve element I00 is provided with a cross-passage I04 and a slot I05. A groove I00 cooperates with a stake pin IOI (Fi ure 17) to hold the valve element in the bore. When the valve is in a position where the crosspassage I04 places passage 96 in communication with a passage I06 leading to conduit 80, slot I05 will be in a position to prevent connection between 85 the passage'98 and passage I06. When the valve element is turned in a clockwise direction in order to shut off passages I04 and 96, passage 98 will be in communication with passage I06. The casing 85 is also provided with a vertical bore I01 with which passage I06 communicates. Within this bore is a valve element I08 which is the movable valve element of the restricting valve C. This valve element has an annular recess I09 for controlling communication between the passage W6 and port IIO to which is connected conduit 80 leading from the valve D. The valve element I08 is normally biased downwardly by a spring III interposed between the valve element and a closure plug H2. The lower end of the 60 valve element projects out of the bore and is adapted to be engaged by acam -I I3 in the form of a lug' carried on arm 30 which is secured to shaft 29 (see Figure 9). This cam II3 when engaging the valve element I08 moves it upwardly I so as to restrict only the flow of air between passage I06 and the port IIO. When cam II3 permits the valve element to move downwardly under the action of spring III, there will be no restriction of flow of fluid between passage I06 and port IIO.

In order to prevent either the combined low and reverse gear l6 or the clutch'collar 2| from being placed in an operative position when the other is in operative position, I have also embodied in my control mechanism an interlocking mechanism which has combined therewith yieldable detent means for holding either the combined low and reverse gear or the clutch collar in their different positions. The structure employed is shown 7 in detail in Figures 10, 19 and 20. The arm 21, to which the shifting fork 28 is pivotallymounted, is provided with a flange I I5 and likewise the arm 3|, to which the shifting fork 32 is pivoted, is provided with a flange H4. Flange H4 has three recesses H5, H1 and H8, and flange II5 has three recesses II9, I20 andv I2I. Positioned between the flanges is a T-shaped member I22 pivotally mounted on the inside of the closure plate by a pin I23 (see FigurelO). The cross leg of this length as to permit only one of the balls to be moved out of a recess at one time. l

The flange II4 on each side'of recess III is, provided with flat surfaces. I20 lying in asingle plane, and likewise flange I It on each side of the central recess I20 is provided with flat surfaces I80 lying in a single plane. The surfaces on each side of the recesses IIB, II8, H9 and I2I are curved and when presented opposite a flat surface, themember I22 is not pivotally movable as when the flat surfaces are opposite each other. These surfaces are adapted to cooperate with the cross leg of member I22 for locking a shifting fork in a neutral position whenever the other shiftin fork is moved out of a neutral position to place a transmission element in operative position. This is best shown by reference to Figures 19 and 20. In Figure 19 the parts are in the neutral position of the transmission and, therefore, ball I25 is in the central recess I20 and ball I28 is in recess 1. Under these conditions themember I22 has a predetermined amount of pivotal play between the flat surfaces I29 and I30. However, when arm 3I is, for example, rotated so as to place the clutch collar 2i in high speed position, ball I26 will be placed in recess II8 (Figure 20). Because of the curved contour of the flange II4 on each side of said recess II8, the member I22 will now be forced against the flat surfaces I30 thereby making it-impossible for arm 21, which carries flange I I5, to be rotated. The same condition would prevail if arm 3i were rotated so as to place ball I28 in recess H6. On the other hand if arm 3I is in neutral position and arm '21 rotated so that ball I25 would rest either in the recess I19 or recess I 2|, then member I 22 would be forced, by the curved contour of flange H5, into engagement with the flat surface I29. Under these conditions arm 3I cannot be rotated.

The ends of flange IIfl are provided with stops I3I for engagement with the member I 22 to limit the relative movement of arm 3| in either direction. Similarly, stops I32 are provided on flange I I5 for cooperation with member I22 to limit the Since balls I25 and I2 6 are spring-pressed into the recesses, they will tend to hold arms 21 and iii in all positions they may assume in controlling the transmission.

Referring now to the operation of my novel control mechanism, the transmission, when in neutral position, will be as shown in Figures 1 and 6. In Figure 1 the clutch pedalwill be in clutch-engaged position when in the right-hand dotted position and in clutch-disengaged position when moved to the central position also indicated by a dotted line. The clutch is also disengaged when the clutch pedal'is fully depressed as shown' in full lines in Figure 1. In the neutral condition will be in a position where the indicating finger 56 is in the N position. .The shaft 44 will be biased downwardly in order to connect it with arm 42, as shown in Figures 12 and 13.. If the vehicle is tion. 25 When it is desired to place the transmission in tion. the fly-weights will be in the position shown in Figure 8.

If it is desired to shift into reverse gear drive,

5 the clutch pedal is depressed either to its central position or to its full position, as shown in Figure 1. The raising of the valve element 81 by the clutch pedal will have no effect in connecting the suction motor to the manifold since the valve elel ment I00 is closed as shown in Figures 3 and 17.

Next, the handle 50 is pulled toward the steering wheel to thus axially move shaft 44 upwardly in order to connect it with arm 48. The gear shifting handle is then rotated in a counter-clockwise I direction to place the finger at the end of the slot marked E. This movement of the handle will cause shaft 40 to be rotated and by means of rod 4|,arm 20, shaft 20, arm 21, and shifting fork the combined low and reverse gear I0 will be 20 moved rearwardly into engagement with the reverse gear idler It. When the clutch pedal is released to engage the clutch, the engine will be capable of driving the vehicle in a reverse direclow speed ratio, the clutch is first disengaged and then, the gear shifting handle is moved to place the finger in the end of the slot marked Lo."

This will cause the low and reverse speed gear I6 to be shifted forwardly by means of the same connection employed in shifting the gear rear-.1

wardly. The gear I6 is then meshed with gear I2. When the clutch is engaged, the wheels of the vehicle will be driven forwardly through the: 35 low speed gear ratio. Low gear position is shown in Figure 3 (clutch pedal in initial disengaged position J During low speed ratio driving the countershaft is rotated with the wheels of the vehicle and,

40 therefore, ,the fly-weights of the governor will have a tendency to be thrown outwardly due to the rotation of shaft 25 upon which they are pivotally mounted. These weights, however, will not be thrown outwardly against the action of spring 5 10 until the speed of the vehicle reaches a value of approximately .18 miles per hour. As long as the weights remain in their closed position, as

shown in Figure 8, the rear end of the suction motor cylinder will be in communication with conduit 00 leading from the manifold through the valves A, B, and' C. The forward end of the cylinder of the suction motor, due to the position'of the valve element I3, will be connected to atmosphere through port I'I, casing 63, and atmospheric port I1. Suchtion will not be effective in the rear rotative movement of arm 21 in either direction. 2

end of the cylinder of the suction motor under these conditions due to the fact that the valve element. of valve A is in its lower position as shown in Figure 3, this lower position being the normal position of the valve whenever the clutch pedal is in a position to engage the clutch or is depressed to'its central position shown in dotted lines in Figure 1.- It is only when the clutch pedal is moved beyond the initial clutch-disengaged position and to a position where the foot pad is 7 ends of the cylinder of the suction motor. Howof the transmission the gear shifting handle 55 i 0 closed, as shown in Figure 3, as longllas the g ear stopped when the transmission is in neutral'posishifting handle is in its neutral position or in either the low or reverse speed position. However, when the gear shifting handle is moved in order to place the indicating finger 56 in the end of the slot marked Hi, the valve element 180 of valve B will be caused to assume an open position as shown in Figures 4 and 5 and the levers 33 and 34 will move outwardly away from each other to their limit of travel as shown. I

With the vehicle now moving and the'transmission in low speed ratio and it is desired to place .the transmission in one of its top speed ratios (second or direct drive) which is marked Hi, the clutch is disengaged by moving the clutch pedal to its fully depressed position, shown in full lines in Figure 1, this position being beyond the position where the clutch is initially disengaged. Next, the gear shifting handle is moved so that the indicating finger is moved out of the end of the slot marked L to the N position, thus disengaging the combined low and reverse gear Hi. When the indicatingfinger is in the position marked N, spring will be permitted to operate to move the shaft 44 downwardly and thus place finger 5B in a position so that it can move into the end of the slot marked Hi." The action of the spring also disconnects arm '63. from the shaft and connects arm 42 to the shaft. Clockwise rotation of handle 55 now causes arm 42 to be'rotated and with it arm 39 through the connecting rod Ml. The arm 39 will be moved in a clockwise direction as viewed in Figure 1 and since the companion levers 36 and 35 are controlled by this arm, they will be simultaneuosly moved away from each other to the limit of their travel and to the positions shown in Figures 4 and 5. Since the valve elementlflll of valve B is connected to leveriit, movement of this lever will place said valve element in the position shown in Figures f1 and 5 which permits air from the suction motor to be drawn into themanifold, provided, of course, the valve element 81 of the valve 'A is open which will be the case since the clutch pedal is fully depressed. Thus by the opening of valve element I00 of the conditioning valve B the power shifting means is conditioned for operation.

. The moving of valve element I00 to the position shown in Figures 4 and 5 causes slot I05 to be moved to such a position that passage 98 leading to atmosphere will be out off from conduit 80 leading to the suction motor through valve D; Thus it is seen that with the clutch pedal fully depressed and the gear shifting handle moved so that finger 56 is in the end of the slot marked Hi, the manifold will be in direct communication with conduit 80. The valve element l0 of valve C will be effective to restrict flow of air from conduit 80 to the manifold since under these conditions the cam H3 will hold the valve element upwardly in the position shown in Figure 17, this being the position corresponding to the neutral position of the clutch collar 2| and its shifting fork 32.

Assuming that the speed of the vehicle is below the selected value of 18 miles per hour, then as soon as the gearshifting handle assumes a position where the finger is in the end of the slot marked Hi, the suction of the manifold will be efiective to draw air out of the rear end of the cytinder of the suction motor since the valve element 13 of valve D is in the position shown in Figure 8. The front end of the cylinder is in communication with the atmosphere and, therefore, the piston of said motor will be moved rearwardly and this will cause arm 30 to be rotated in a clockwise direction as viewed in Figure 1. Rotation'of this arm will cause the shifting fork 32 and the clutch 'collar to be moved rearwardly as viewed in Figure 6. This will cause the synchronizer membbr to be operated and the teeth of the clutch collar to engage clutch teeth IQ of gear I! to connect said gear to the driven shaft and thereby obtain second speed ratio. The movement of the piston of the suction motor will be fairly slow at the beginning of the stroke due to the fact that the valve element N8 of valve C restricts the fiow of air from the suction motor. However, as soon as the shifting fork has been moved a suflicient distance to permit cam H3 to move .out from beneath the valve element 108, this valve element will have less restricting action and the air in the suction motor will be pulled out at a greater rate. Thus the piston will apply greater power which will be sufllcient to operate the synchronizer and place the clutch collar in a position to connect the gear to the driven shaft. With the transmission in second speed ratio, the clutch can now be released to permit power to be appplied to the wheel of the vehicle. When the clutch is released, the valve element 81 of valve A is returned to its lower position, thereby cutting off the suction motor from the manifold.

If the speed of the vehicle is above the selected speed of 18 miles per hour when the clutch pedal is fully depressed and the finger of the gear shifting handle is placed in the end of the slot marked Hi, then the valve element 13 of valve D will be in the position indicated in Figure 9 due to the fact that the fry-weights 68 are thrown outwardly againstthe action of spring 10. This position of valve element '13 results in the forward end of the suction motor being in communication with conduit 80 leading to the manifold instead of the rear end of the cylinder, said rear end now being in communication with the atmosphere through the passage 79, the casing 53, and the atmospheric port ii. The piston will now be moved forwardly instead of rearwardly and consequently the shifting fork 12 will be shifting forwardly and thus cause the clutch collar to connect the driving shaft directly with the driven shaft. Thus it is seen that high speed ratio will be obtained and the second speed ratio will be skipped. I

If the transmission should be in second speed, as already described, and high speed ratio is then desired, such speed cannot be obtained until the speed of the vehicle reaches a value above the selected speed of 18 miles per hour. However, when the speed of the vehicle is right (above 18 miles per hour) all that is necessary to obtain high speed or direct drive is to depress the clutch pedal fully beyond the initial clutch-disengaged position. This will cause the valve element 8'! of valve A to be placed in open position in order to connect the forward end of the cylinder of the suction motor to the manifold to accomplish the shift.

As the piston of the suction motor moves from the rear end of the cylinder to the forward end thereof, it will pass through the. central position which is the disengaged or neutral position of the clutch collar. As the piston approaches the central position, cam 3 will become operative to move the valve element I08 of valve C upwardly and restrict the flow of air between conduit 80 and the manifold. This will slow up the movement of the piston and permit time for proper operation of the synchronizing means associated with the clutch collar. As soon as the piston begins to approach the forward end of the cylinder, cam H3 will move from beneath the valve element I08- and allow air to be pulled out of the suction motor at a greater rate to complete the shift. It is thus seen that the restricting action of valve element I08 is very effective in producing a quiet shift without the clashing of teeth by permitting slower action and time to allow for operasuction motor with the manifold. Disengaging the clutch will in ,no way affect the high speed condition. However, if the speed of the vehicle should drop below the 18 miles per hour, then the valve element 13 will assume the position shown in Figure 8 and connect the rear end of the cylinder of the suction motor to conduit, 80 leading to the manifold. If the clutch pedal is arises, second speed gear is obtainedby depressing the clutch pedal and then moving the gear shifting handle to the position where the finger is opposite N. The transmission is now discon nected from the engine and also from the wheel of the vehicle and, therefore, the countershaft is no longer driven. The oil of the transmission will slow down the speed of the countershaft quite rapidly and when it reaches a point where 1 the fiy-weights assume their closed position, the valveelement 13 of valve D will be in a position to connect the rear end of the cylinder of the suction motor to conduit 80 leading to the manifold. If' the gear shifting handle is now moved to again'place the finger in the end of the slot marked Hi and the clutch pedal is fully depressed (if not already so depressed) the suction fully depressed under these conditions, the piston of the suction motor will be moved to the rear end of the cylinder and the transmission then placed in second speed condition in a manner already described. Whenever the transmission is shifted from either second speed ratio to high speed ratio or from high speed ratio to second speed ratio, the restricting valve 108 will always be operated to properly slow down the speed of movement of the piston of the suction motor as it passes through the intermediate portionof its path of travel from one end of the cylinder to the other..

- When it is desired to place the transmission in neutral with either second speed ratio or high speed ratio operative, all that is necessary is to move the clutch pedal to a position where the clutch is either initially disengaged or to its fully depressed position and then move the gear shifting handle to a position where the indicating finger is opposite N. This will cause the two companion levers 33 and 34 to be moved toward each other and if the transmission is in high, lever 34 will pick up the shifting fork 32 and move the clutch collar to the neutral position. If the transmission is in second speed ratio, lever 33 will pick up the shifting fork 32 and move the clutch collar to neutral position. As soon as lever 34 begins to move toward lever 33 and before the shifting fork is picked up by either lever 33 or 34, it will rotate valve llllland cause slot I 05 to connect conduit 80 with the atmosphere through conduit 85. Both ends of the, cylinder of the suction motor will now be connected to atmosphere regardless of the position of the valve element 13 of valve D. This will permit the piston of the suction motor to be easily moved with the shifting motor will operate in order to connect the second speed gear to the driven shaft. By immediately releasing the clutch pedal, second speed gear ratio will remain engaged since the suction motor will be cut off from the manifold. Thus any speeding up of the countershaft to again shift the valve element 13 of valve D back to the position shown in Figure 9 will not change the speed ratio.

The interlocking and detent mechanism functions in a manner already described. The'springpressed balls hold the shifting forks in both their neutral and operative positions. Also, the interlocking pivoted member I22 prevents either shifting fork from being moved from neutral position whenever the other shifting fork is in an operative position.

From the above description it is apparent that I have produced a change speed transmission control mechanism which permits the operator to properly control the transmission at all times and with a minimum of effort. The low and reverse gear ratios are manually controlled which is not objectionable since these gear ratios'are used less than the other gear ratios. and second gearjatios are semi-automatically controllable. One setting of the gear shifting handle is all that is required for both speed fork 32 to its central position where the clutch collar is disengaged. It is thus seen that the transmission can always be neutralized regard-- less of its operative condition by merely moving the handle to a position where the indicating finger is opposite the point marked N.

By having the fiy-weights connected to be convehiclefmay b greater than 18 miles per hour. This condition may ariseif the vehicle is going down-hill'in high speed and it is desired tdget" it in second speed gear. When such a condition ratios. The selection of the speed ratio of these two top speeds is made by the speed of the vehicle biit the actual change is not made except at the will of the operator. Thus one is able to obtain the speed ratio he desires but then onlyif such a speed ratio is proper for a given speed of the vehicle. If it is desired to remain in high speed ratio, one can do so notwithstanding the speed of the vehicle drops to a value to select second speed ratio. Also, if it is desired to remain in second speed ratio and speed up the vehicle above the point where high is selected, such can be done. The actual shifting is accomplished quickly and easily by merely fully depressing the clutch pedal. Once the gear shifting handle is set in the Hi position it need no longer be touched unless itis desired to obtain low gear, reverse gear or neutral. Also, there is no dangerof the operator not knowing the operative or inoperative condition of the transmission. He knows positively that it will bein neutral whenever the finger 56 points to N. Also, it is possible by means of the control mechanism to skip"second speed gearratio when starting'the vehicle from a stopped position if such is desired; All that need be doneis to speed up the carin low gear I and then'fully depress the clutch pedal;

f Being aware of the possibilitypflhodiiications in theparticular'structure herein describedwith out departing from the fundamentalprinciples The high means responsive to the speed of a member of the transmission for determining which gear ratio will be established by the pedal-controlled means when operated, manual means independent of the clutch pedal for manually neutralizing by operator effort an established gear ratio, and means operable by the manual means when moved to the position to neutralize a gear ratio for preventing the re-establishment of either gear ratio by said clutch pedal controlled means when the clutch pedal is moved to a clutch disengaged position.

2. In a control mechanism for a change speed transmission provided with a member shiftable to two positions in opposite directions from a central neutral position to thereby obtain different speed ratios, a power-operated device for shifting said member, means for conditioning the power-operated device for operation, speed responsive control means for determining in which direction the power-operated device will 1 shift said member, manually-controlled means for causing saidpower-operated device to operate, other independent manually-controlled means operable at will for causing said shiftable member to be placed in its neutral position when in an operative position but incapable of placing the shiftablemember in an operative position by manual effort, said last named means including a mechanical connection for transferring manual effort to the shiftable member and means for controlling the conditioning means by the independent manually-controlled means so that it will be conditioned when said manually controlled means-is in a position other 1 than neutral position.

3. In a control mechanism -for a change speed transmission provided with two gear ratios, a power-operated device for establishing either of said two 'gear ratios, control means for determining which gear ratio the power-operated device will establish, means for conditioning the power-operated device for operation, movable control means for causing said power-operated device to operate, other independent manuallycontrolled means operable at will for causing by manual effort the neutralizing of an established gear ratio but being incapable of establishing a gear ratio by. manual effort and means for controlling the operativeness of the conditionin means by said other independent manuallycontrolled means when in other than neutral position.

4. In a control mechanism for a change speed gearing provided with a member shiftable to two positions in opposite "directions from a central neutral position to thereby obtain different speed ratios, means comprising a single movable element for moving said member to its operative positions, means for disabling said moving means, control means for said moving means, two members movable in opposite'directions. said members when moved to positions adjacent each other cooperating with the shiftable member to asses place it in neutral position and when moved to positions away from each other permitting said shiftable member to be freely moved by said moving means therefor, and manually-controlled means forming the sole means for moving said two movable members simultaneously to positions adjacent each other, said manually-controlled means also being connected to operate the disabling means for the moving means prior to moving the two members.

5. In a control mechanism for a change speed gearing provided with a member shiftable to two positions in opposite directions from a central neutral position to thereby obtain difierent speed ratios, means for moving said member to its operative positions comprising a fluid motor, control means for said last named means, two members movable in opposite directions, said members when moved to positions adjacent each other cooperating with the shiftable member to place it in neutral position and when moved to positions away 'from each other permitting said shiftable member to be freely moved by said moving means therefor, manually-controlled means for moving said two movable members simultaneously, and means comprising a valve operable by the manually-controlled means for determining the operativeness of the motor when the two members are moved to positions away from each other and the inoperativeness of the motor when the two members are initially moved to positions adjacent each other.

6. In a control mechanism for a change speed transmission provided with a member shiftable to two operative positions to establish two gear ratios, a power-operated device for establishin the gear ratios, means for conditioning the poweroperated device for operation, control means for causing said power-operated device to be operated ling the conditioning means by the last named manually-controlled means when in other than neutralizing position.

'7. In a control mechanism for a change speed transmission provided with means whereby either of two gear'ratios may be made operative or inoperative, means including a fluid motor for establishing said gear ratios, control means including a manually-controlled valve for causing said motor to establish either of said gear ratios, and manually-controlled means independently operable of the last named control means for disabling the operation of the fluid motor by its control means and for thereafter manually causing at will either of the gear ratios to be inoperative.

8. In a control mechanism for a change speed transmission provided with means whereby either of two gear ratios may be made operative orinoperative, means including a fluid motor for establishing said gear ratios, control means including a manually-controlled valve'for causing said motor to establish either of said gear' ratios, manually-controlled means independently operable of the last named control means for manually causing at will either of the gear ratios to be inoperative, and valve means movable by the manually-controlled means to a closed position for pretransmission prvided with a member shiftable to venting the motor from being operated when the gear ratios are caused to be inoperative.

9. In a control mechanism for a change speed transmission provided with a member shiftable to two operative positions toestabllsh two gear ratios, a power-operated device for shifting said member, control means including a control device controllable at will to a single operative position for causing said power-operated device to move said member to an operative position, manuallycontrolled means settable in one position for conditioning said control means to cause operation of said power means and settable in another position for preventing said controlm'eans from causing operation of said power means, and means operable when said manually-controlled means is moved to the last named settable position from the first named settable position for causing by manual effort an operative gear ratio to be inoperative.

10. In a control mechanism for a change speed transmission provided with two gear ratios, a fluid motor connected to establish either gear ratio, a source of differential pressure, alve means for selectively connecting the opposite ends of the motor to the source, two other valve means each of which is capable of placing the source in com munication with the motor through the selective valve means and cutting it 01f, movable control means for controlling one of said other valve means, and independent manual means for controlling the second of said other valve means, said last named manual means also being operatively connected to the transmission to cause an operative gear ratio to be neutralized by a manual force after said manual means is moved to a position causing its valve means to be in a cut off position.

11. In a control mechanism for a change speed transmission provided with means whereby two gear ratios may be made operative or inoperative, a fluid motor for establishing either of, said gear ratios, a source of difl'erenti'al fluid pressure, conduit means between said source and the motor, speed responsive controlled valve means associated with said conduit means for connecting said source to the motor so as to cause the motor to be operated in opposite directions, a manuallysaid speed responsive control valve means and the source, a third valve means, manual means for controlling said third valve means, and means operable by said manual means when in valve closed position for manually causing at will either of the gear ratios to be inoperative,

controlled valve in said conduit means between two positions in posite directions from a central neutral position t thereby obtain different speed ratios, a main cl u operating pedal, 'asuction motor connected to the shiftable member, a source of suction, conduit means between the source and opposite ends of the motor, three valves positioned in series in said conduit means for controlling the operation of'the suction motor, one

of said v'alves being movable to two positions to alternately connect opposite ends of the motor to the source, the other two of said valves each being movable to either open or close said conduit means, means for controlling one of said two valves by the clutch pedal so as to be closed when the clutch is engaged and open when the clutch is disengaged, other manual means settable in two positions for opening and closing the second of said two valves, and a mechanical connection between said last named manual means'and the shiftable member for causing said shiftable member to be manually placed in neutral position when said manual means is set to cause the valve controlled thereby to be closed.

14. In a control mechanism for a change speed transmission provided with a member shiftable to two positions in opposite directions from a central neutral position to thereby obtain different speed ratios, a main clutch operating pedal, a

suction motor connected to the shiftable member, a source of suction, conduit means between the source and opposite ends 01. the motor, three valves positioned in series in said conduit means for controlling the operation of the suction motor, one

of said valves being movable to two positions to alternately connect opposite ends of the motor to the source, the other two of said valves each being movable to either open or close said conduit means, means responsive to the speed of a member of the transmission for controlling the position of said first valve, means for controlling one of said two valves by the clutch'pedal so as to be closed when the clutch is engaged and open when the clutch is disengaged, other manual means settable to two positions for opening and closing the second of said two valves, and a mechanical connection between said last named manual means and the shiftable member for causing said shiftable member to be in neutral position when said manual means is set to cause the valve controlled thereby to be closed, said mechanical connection beinginefiective to move said shiftable member from a neutral position to an operative 12. In a control mechanism for a change speed transmission provided with a member shiftable to two positions in opposite directions to thereby obtain dififerent speed ratios, a suction motor connected to the shiftable member, a source of suction, conduit means, between the source and opposite ends of the motor, three valves positioned in series in said conduit means for controlling the operation of the suction motor, one of said valves being movable to two positions to alternately connect opposite ends of the motor to the source, the other two of said valves each being movable to either open or close said conduit means, manual means for controlling one of said two valves, other independent manual means for controlling the second of said two valves, and a connect on from saidlast named manual means for causing an operative gear ratio to be neutralized by manual eflort when said controlled valve is closed.

13. In a control mechanism for a change speed position.

15. In a control mechanism for a change speed transmission provided with one member shiftable to two positions for obtaining low and reverse speed ratios and a second member shiftable to two positions for obtaining second and high speed ratios, a manual member mechanically connected to manually shift the first member to either position and comprising the sole shifting means therefor, means for shifting the second member to,

ting said driver controlled means to control the shifting means.-

16. In a control mechanism for a change speed transmission provided with one member shiftable to two positions for obtaining low and reverse speed ratios and a second member shiitable to two positions for obtaining second and high speed ratios, a manual member mechanically connected to manually shift the first member to either position, means for shifting the second member to either position, speed responsive means driven by amember of the transmission for'determining to which position said second member willbe shifted by its shifting means, driver controlled means for causing said shifting means to be operative, means controlled by the manual member when placed in a position other than neutral or a position operating the first named shiftable member for permitting said driver controlled means to control the shifting means, and means controlled by said manual member when placed instill another position for positively causing the second shiftable member to be placed in an inoperative position by manual efiort.

17. In a control mechanism for; a change speed transmission provided with one member shiftable to two positions for obtaining low and reverse speed ratios and a second member shiftable to two positions for obtaining second and high speed ratios, a manual member connected to manually shift said first member to either position, a clutch pedal, means controlled by the clutch pedal when moved to disengaged position for shifting said second member, means for conditioning the last named means for operation, and means operable by the manual member when placed in a position other than neutral or a position operating the first named shiftable member for controlling the conditioning means and permitting said clutch pedal controlled means to' be operated by movement of the clutch pedal,

member when placed in a position other than neutral or a position operating the first named shiftable member for permitting said control means to control the operation. of the motor.

20. In a control mechanism for a change speed transmission provided with one member shiftable to two positions for obtaining low and reverse speed ratios and a second member shiftable to two positions for obtaining second and high speed ratios, a'manual member connected to shift said first member to either position, a fluid motor connected to shift the second member to either posi- *tion, a source of differential pressure connected to operate the motor, control means for the motor second shiftable member to be inoperative by 18. In a control mechanism for a change speed I transmission provided with one member shiftable .to two positions for obtaining low and reverse speed ratios and a second member shiftable to two positions for obtaining second and high speed ratios, a manual member connected to manually shift said first member to either position, a clutch pedal, means controlled by the clutch pedal when moved to disengaged position for shifting said second member, means operable by the manual member when placed in a position other than neutral or a position operating the first named shiftable member for controlling means permitting said clutch pedal controlled means to be operated by movement of the clutch pedal, and means onerable by the manual member when set in still another position for manually moving the second shiftable member to an inoperative position if operative and for also disabling the clutch pedal controlled means so as to be' inoperative when the clutch pedal is moved to clutch disengaged posi- I ally-operated member for manually establishing operator efiort.

21. In a control mechanism for a change speed transmission provided with two gear ratios, a power-operated mechanism for establishin either of said two gear ratios, operator-operated means settable in a predetermined position for conditioning the power-operated mechanism for operation, control means for causing said poweroperated mechanism to operate, means for determining which gear ratio the power-operated mechanism will establish when the control means is operated, and'means operated by the operatoroperated means when moved from said predetermined position to another position for causing by operator effort the neutralization of an established gear ratio, said last named means being operable solely by operator effort and not actuated by the power-operated mechanism for establishing the speed ratios.

22. In a control mechanism for a change speed transmission provided with two gear ratios, a power-operated mechanism for establishing either of said two gear ratios, control means for causing said power operated mechanism to operate, means for determining which gear ratio the power-operated mechanism will establish when the control means is operated, operator-operated means operable at will and independently of the control means for the power-operated mechanism for causing by operator effort the neutralization of an established gear ratio, said last named means being operable solely by operator effort and not actuated by the power-operated mechanism for establishing the speed ratios and means so controlled by the operator-operated means that the power-operated mechanism will be disabled before the gear ratios are manually neutralized by the operator-operated means.

23. In a control mechanism for a change speed transmission having at least three gear ratios, means comprising power-operated means for establishing either of two of said gear .ratios, manually-operated control means operable at will for controlling the operation of the power-operated means, means including independent manuand neutralizing the other speed ratio, means for conditioning said power-operated means for operation by a movement of the last named manuallyoperated member to a position other than that required to establish the said other speed ratio, and means for manually neutralizing either of transmission provided with a member shiftable said' two gear ratios at will by operator efiort and by a return movement of the said independent manually-operated member to the position where the said other speed ratio is neutralized.

24. In a control mechanism for a change speed transmission having at least'three gear ratios, means comprising power-operated means for establishing either of two of said gear ratios, means including a manually-operated member for manually establishing and neutralizing the other speed ratio, means for conditioning said poweroperated means for operation by said manuallyoperated member when moved to a position other than where said other gear ratio is either established or neutralized, means for controlling the operation of the power-operated means, at will, and means for manually neutralizing either of said two gear ratio and disabling the poweroperated means at will by a return movement of the manually-operated member to neutral position.

25. In a control mechanism for a change speed transmission provided with two gear ratios, control means for establishing said gear ratios including a power-operated member movable back and forth between two operative positions and through a central inoperative position, a manual shut-oil valve, and means operable by a move-' ment of said other manually operable means from its shut-off valve open positionfor causing the shut-oil valve to be, closed, said shiftable member to be placed in neutral position by manual efiort only andthe movable element of the power cylinder to be placed in its central position by manual effort.

29. In a control mechanism for a change speed transmission provided with a member shiftable to two gear ratio operative positions and to a neutral position. means for shifting said member comprising a fluid motor having a movable element, means for connecting said movable element to the shiftable member so that the movable element of the fluid motor will be in a cenmember independent of the control means and having a normally inoperative position, means operable by said manual member when moved from the inoperative position to another position for conditioning said control means to be operative, and mechanical connecting means operable when the manual member'is moved back to its inoperative position for first disabling the power-operated member and then positively neutralizing by manual effort either gear ratio if operative and independently of any operation of the control means and to also place the power.- operated member in the central inoperative position. v

26. In a control mechanism for a change speed ative gear ratio..

27.-#In a control mechanism for a change speed transmission having more than two speed ratios with two of the ratios being controlled by one shiftable member and at least another speed ratic being controlled by another shiftablemember, power means for shifting said first shiftable member to cause either of the two speed ratios to be operative, control means for the power means, a manually operable lever having a neutral position, means for manually moving the other shiftable member to an operative position by a movement of the lever from its neutral position, and means for conditioning the control means for optransmission having two different gear ratios, a

'element connected to the member for shifting eration by a movement of the lever to a second position other than neutral so that said control means can be controlled to cause the power means to alternately shift the shiftable member of the two speed ratios, said conditioning means being so manually-controlled by the lever that said power means is inoperable by its control means whenever the lever is in neutral position.

28. In a control mechanism for a change speed tral position between its limits of reciprocable movement when the shiftable member is in neutral position and will cause the gear ratios to be operative when moved in opposite directions from said central position, control means for said fluid motor, manual means having a normally inoperative position, means operable by said manual means when moved from said normally inoperative position for conditioning the control means so that it can control the fluid motor, and means operable by said manual means when returned to its normally inoperative positionfor disabling the control means for the fluid motor, for manually restoring the movable element of the fluid motor to its central position and for i manually moving the shiftable member to its neutral position.

30. In a control mechanism for a change speed transmission provided with a member "shiftable to two gear ratio operative positions and a neutral position, a fluid motor having a movable said member from one operative position to the other through the neutral position, a source of diiferential pressure connected to the motor, valve means for controlling the operation of said fluid motor, means for actuating said control valve means to cause the fluid motor to shift the shiftable member from one operative position to another, a conditioning valve between the source and motor, manual means for causing operation of said conditioning valve to a position where the control valve means when operated by the actuating means will cause operation of the fluid motor or to another position where the conditioning valve cuts oh? the source and also frees the fluid motor of fluid forces acting on itsmovable element, and means operable when the manual means causes operation of the conditioning valve to said other position for neutralizing the transmission and shifting control by manual efiort.

31. In a control mechanism for a change speed transmission having two different gear ratios, a fluid motor for establishing said gear ratios, a

control valve means, a manually operated member for controlling the valve means, a shut-oil valve, a second manually-operated member mechanically connected to said shut-01f valve to,

open it. by a predetermined movement, a speed responsive controlled valve for determining the direction of movement of the movable element of the motor and the gear ratio established and means operable when the said second manuallyoperated member is moved to close said shutoff valve for subsequently causing neutralization of an operative gear ratio'by operator efiort.

32. In a control mechanism for a change speed transmission provided with a member shiftable to two gear ratio operative positions through a neutral position, means comprising control means for shifting said member alternately to its two operative positions, a manual member independent of the control means and having a normally inoperative position, means operable by said manual member when moved from the inoperative position to another position to condition said control means to be operative, and mechanical means between the manual member and the shiftable member which is operable only'when the manual member is moved back to its inoperative position for positively moving by operator efiort the shiftable member to its neutral position from an operative position independently of operation of the control means and after the conditioning means is caused to be inoperative.

33. In a control mechanism for a change speed transmission provided with a member shiftable to two gear ratio operative positions and a central neutral position, power-operated means including a movable member connected to the shifting member and movable back and forth between two operative positions and through a central inoperative position corresponding to the operative positions and the central neutral position of the shiftable member, means comprising control means for causing said power-operated member to operate, a manual member independent of the control means and having a normally inoperative position, means for conditioning the control means so that when operated it will cause operation of the power-operated means, means operable by said member when moved from its ated, means, means operable by said manual member whemmovedifr'om:itsxinoperative position to another; positionifor causing the conditioning meansto be operative, and means operinoperative position to another position for causable when the manual member is moved back to its inoperative position for so controlling the conditioning means as to disable the control means and for also causing the moving of the shiftable member and the movable member of the poweroperated means from their operative positions to their central inoperative positions independently of any operation of the control means.

35. In a control mechanism for a, change speed transmission provided with a shiftable member having two speed ratio operative positions and a neutral*position, a power-operated mechanism connected to the shiftable member for establishing either of said two speed ratios, a source of power energy connectable to the power-operated mechanism, control means including a movable means for controlling the connecting of the power-operated mechanism to the source so as to cause the power-operated mechanism to operate when desired, conditioning means for the control means for permitting said control means when operated to cause operation of the poweroperated mechanism, said conditioning means being independent of any control of the availability of power energy from the power source and when inoperative preventing the source of power energy from being connected with the power means notwithstanding the condition of the control means, operator-operated means movable from one position to another to cause the conditioning means to be in an operative position where the movable means of the control means can control operation of the power means, and other means controlledby the operator-operated means when moved back to said one position to cause a neutralization of a speed ratio after the conditioning means has disconnected .the power-operated mechanism from the source which speed ratio the fluid motor will establish,

transmission provided with a member shiftable I to two gear ratio operative positions and a central neutral position, power-operated means including a movable member connected to the shifting member and movable back and forth between two operative positions and through a central inoperative position corresponding to the operative positions and the central neutral position of the shiftable member, means comprising,

ated it will cause operation of the: power-operconditioning valve means for the control means having an open operative position for permitting said control means when operated to cause operation 'of the motor and an inoperative closed position disabling the motor and connecting it to atmosphere, operator-operated means movable from one position to another to cause the conditioning valve means to be moved from an inoperative position to an operative position, and other means controlled by the operator-operated means when moved backtosaid one position for causing after the conditioning valve means has been made inoperative a neutralization of an established speed ratio, said neutralization being accomplished by a force independent of any force from the fluidimotor-i GLENN 'I'L. RANDOL. 

